According to studies reported by the Centers for Disease Control and Prevention (CDC), the National Health and Nutrition Examination Survey (NHANES) and the National Health Interview Survey (NHIS), more than two-thirds (68.8 percent) of adults over 20 years of age are considered to be overweight or obese. Additionally, more than one-third (35.7 percent) of adults are considered to be obese and more than 1 in 20 (6.3 percent) have extreme obesity.
Additionally, the National Institute of Health reports that overweight and obesity are risk factors for type 2 diabetes, heart disease, high blood pressure, and other health problems such as nonalcoholic fatty liver disease (excess fat and inflammation in the liver of people who drink little or no alcohol), osteoarthritis (a health problem causing pain, swelling, and stiffness in one or more joints), some types of cancer including breast, colon, endometrial (related to the uterine lining), and kidney, as well as stroke.
Not exclusively a United States problem, worldwide obesity ranges are also increasing dramatically. The World Health organization reports that Worldwide obesity has more than doubled since 1980 and in 2014, more than 1.9 billion adults, 1.8 years and older, were overweight. Of these over 600 were obese.
There is no single cause of overweight and obesity, and, although the physiology and psychology of obesity are complex, the medical consensus is that the key contributing factor is an over intake of calories combined with reduced energy expenditures. There is no single approach that can help prevent or treat overweight and obesity. Conventional treatments may include a mix of behavioral therapy, diet, exercise, and sometimes weight-loss drugs. In some cases of extreme obesity, weight-loss surgery may be a preferred option.
Bariatrics is the field of medicine encompassing the study of overweight and obesity, its causes, prevention and treatment. Bariatric surgery is a treatment for morbid obesity that involves the surgical alteration of a patient's digestive tract to encourage weight loss and to help maintain normal weight. Known, conventional bariatric surgical procedures include jejuno-ileal bypass, jejuno-colic shunt, biliopancreatic diversion, gastric bypass, Roux-en-Y gastric bypass, gastroplasty, gastric banding, vertical banded gastroplasty, and silastic ring gastroplasty.
There have been many attempts in the past to surgically modify patients' anatomies to attack the over consumption problem by reducing the desire to eat. Stomach stapling, or gastroplasties, to reduce the volumetric size of the stomach, therein achieving faster satiety, were performed in the 1980's and early 1990's. Although patients undergoing such procedures were able to achieve early weight loss, sustained reduction was not typically obtained. The reasons for these outcomes are not all known, but are believed related to several factors. One of which is that the stomach stretches over time increasing its volume while psychological drivers motivate patients to find creative approaches to literally eat around the smaller pouch.
There are two conventional surgical procedures that have been observed to successfully produce long-term weight loss; the Roux-en-Y gastric bypass and the biliopancreatic diversion with duodenal switch (BPD). Both procedures reduce the size of the stomach plus shorten the effective-length of intestine available for nutrient absorption. Reduction of the stomach size reduces stomach capacity and the ability of the patient to take in food. Bypassing the Duodenum makes it more difficult to digest fats, high sugar and carbohydrate rich foods. One objective of the surgery is to provide feedback to the patient by producing a dumping syndrome if the patient does eat these food products. Dumping occurs when carbohydrates directly enter the jejunum without being first conditioned in the Duodenum. The result is that a large quantity of fluid is discharged into the food from the intestinal lining. The total effect makes the patient feel light-headed and results in severe diarrhea. For reasons that have not been determined the procedure also has an immediate therapeutic effect on diabetes.
Although the physiology seems simple, the exact mechanism of action in these procedures is not understood. Negative feedback is provided from both regurgitation into the esophagus and dumping when large volumes of the wrong foods are eaten. Eventually, patients learn that in order to avoid both of these issues they must be compliant with the dietary restrictions imposed by and resulting from their modified anatomy. In the BPD procedure, large lengths of jejunum are bypassed resulting in malabsorption and therefore, reduced caloric uptake. In fact, the stomach is not reduced in size as much in the BPD procedure so that the patient is able to consume sufficient quantities of food to effectively compensate for the reduced absorption. This procedure is reserved for the most morbidly obese as there are several known serious side effects of prolonged malabsorption.
Laparoscopic techniques have been applied to these surgeries in an attempt to improve the patient outcomes. While the laparoscopic techniques provide fewer surgical complications, e.g., hospital acquired infections, etc. they continue to expose these very ill patients to high operative risk in addition to requiring an enormous level of skill by the surgeon.
While surgery seems to be an effective answer in the treatment of overweight and obesity, the current invasive procedures present risks that are frequently not acceptable in view of the observed complication rates. Additionally, the medical devices that have been proposed for use in the treatment of overweight and obesity in the literature, as well as the surgical approaches, provide a general approach of malabsorption of all nutritional components of the ingested foods. Further, the most favorable surgical procedure functions by the elimination of contact of ingested food with the absorptive tissues of the Duodenum. The mechanism of the bypass, while not being fully understood, appears to limit the absorption of the carbohydrate and simple sugar components of the ingested food, as evidenced by the generally immediate reduction in the blood sugar levels of treated patients. Additionally, medical devices or newer surgical approaches that demonstrate this reduction of blood sugars are deemed successful, despite the potential creation of generalized malnutrition.
In the article “Dietary Influences on Gastric Emptying of Carbohydrate versus Fat in the Rat”, by Trout et. al., published in the Journal of Nutrition; 107: 104-111, 1977, it was determined that “gravity tends to hold back the fat from leaving the stomach, allowing glucose in aqueous solution to be preferentially emptied” and further that “a sizable portion of the starch in starch-containing meals became suspended in water during and shortly after being ingested, and the starch suspension was then emptied from the stomach preferentially to fat-containing particulate matter”. It would appear that this functionality of the natural separation of the glucose, or solubilized sugars, as well as the suspended starches and the subsequent acceleration of these components through the pyloric valve into the Duodenum could be eliminated and thereby prevent the blood sugar from elevating while not inhibiting the absorption of the necessary dietary nutrients that are critical to cellular survival.
In U.S. Pat. Nos. 4,501,264; 4,641,653 and 4,763,653, Rockey discloses medical sleeve devices for placement in a patient's stomach. The medical sleeve described in these patents is intended to reduce the surface area available for absorption in the stomach without affecting the volume of the stomach, nor will the device described isolate ingested food from stomach secretions. The medical sleeve is not configured to be deployed in a patient's small intestine and will not have an appreciable impact on the digestion of the ingested food.
In U.S. Pat. No. 4,134,405 (Smit), U.S. Pat. No. 4,315,509 (Smit), U.S. Pat. No. 5,306,300 (Berry), and U.S. Pat. No. 5,820,584 (Crabb), sleeve devices are described that are intended to be placed at the lower end of the stomach and therefore do not serve to isolate ingested food from the digestive secretions of the stomach. These sleeve devices are not configured to be deployed in a patient's stomach or to effectively reduce the volume of the patient's stomach or small intestine.
In U.S. Patent Application US 2003/0040804, Stack et al. describe a satiation device to aid in weight loss by controlling feelings of hunger. The patent application describes an antral tube that expands into the Antrum of the stomach to create a feeling of satiation. The devices described are not configured to isolate ingested food and liquids from digestive secretions in the stomach or the intestines.
In U.S. Patent Application US 2003/0040808, Stack et al. describe a satiation device for inducing weight loss in a patient that includes a tubular prosthesis positionable at the gastro-esophageal junction region, preferably below the z-line. The prosthesis is placed such that an opening at its proximal end receives masticated food from the esophagus, and such that the masticated food passes through the pouch and into the stomach via an opening in its distal end. The pouch serves to delay the emptying of food into the stomach, thereby providing the patient a sense of fullness prior to filling the stomach.
In U.S. Patent Application US 2003/0093117, Sadaat describes an implantable artificial partition that includes a plurality of anchors adapted for intraluminal penetration into a wall of the gastro-intestinal lumen to prevent migration or dislodgement of the apparatus, and a partition, which may include a drawstring or a toroidal balloon, coupled to the plurality of anchors to provide a local reduction in the cross-sectional area of the gastro-intestinal lumen. The reduction in the cross sectional area of the lumen delays motility of ingested food, thereby increasing the sense of satiety that the patient experiences.
In U.S. Patent Application US 2003/0120265, Deem et al. describe various obesity treatment tools and methods for reducing the size of the stomach pouch to limit the caloric intake as well as to provide an earlier feeling of satiety. The smaller pouches may be made using individual anchoring devices, rotating probes, or volume reduction devices applied directly from the interior of the stomach. A pyloroplasty procedure to render the pyloric sphincter incompetent and a gastric bypass procedure using atraumatic magnetic anastomosis devices are also described.
In U.S. Patent Application US 2003/0144708, Starkebaum describes methods and systems for treating patients suffering from eating disorders and obesity using electrical stimulation directly or indirectly to the Pylorus of a patient to substantially close the Pylorus lumen to inhibit emptying of the stomach
In US Patent Application 2014/0275747, Connor discloses a device that is comprised of two passages for food to travel through a patient's digestive tract, referred to as an adjustable gastrointestinal bifurcation. The device has two openings that are regulated by a flow control member that may at least partially direct ingested food into either opening. The bifurcated device is comprised of two openings that are located at the superior end of the device just below the esophageal sphincter. The flow control member is capable of adjustment from a remote location and may direct food into either a passage that enables absorption of nutrients or a second passage that limits the absorption of nutrients. While the device can divert various food types, it requires a conscious effort on behalf of the user or physician to set the diversion pathway into the correct location for the specific food type that has been ingested. An alternative form of the device requires the implantation and use of a remote sensor within the upper GI tract to sense the type of food being ingested to direct the flow control member. This would require the presence of an invasive foreign object within the upper GI tract, particularly the oral cavity, which would likely be intolerable to the patient.
In U.S. Pat. No. 7,794,447, Mitchell et. al. describe bypass type tubular devices that may be produced with valves and restrictors to control the exposure of ingested food to digestive secretions. The devices as disclosed form a passage between the upper portion of the stomach, or lower portion of the esophagus, through which ingested food particles will pass. The passage may be produced with valves or increased porosity, enabling digestive secretions to enter the passage to digest the food contained therein and also enabling reverse passage of partially digested nutrients to flow back into contact with the absorptive tissues of the GI tract. The restrictive passage may extend as far as the ileum to allow the discharge of partially digested material into portions of the GI tract that may respond and cause the body to eliminate the undigested food from the GI tract. The device, as disclosed, does not differentiate between healthy and unhealthy ingested materials and primarily functions to limit the digestive processes. In the most restrictive form of the device, difficult to digest materials, such as complex proteins, would pass undigested into the ileum and therefore be eliminated from the body without imparting any benefit to the patient.
There remain unmet needs in this art to provide medical devices that are capable of re-directing the most damaging components of ingested food, that are reversible, that do not inhibit the digestion of healthy components of ingested food, that do not rely on patient inputs to function properly, and that provide negative biological feedback to inhibit the ingestion of simple sugars and carbohydrates.
There also remains a need in this art for less invasive methods of altering patients eating behavior while reducing the dietary impact of foods that are incompatible with diabetic metabolic disorders and novel medical devices for facilitating such methods.